Partially Fire Resistant Insulation Material Comprising Unrefined Virgin Pulp Fibers and Wood Ash Fire Retardant Component

ABSTRACT

A partially fire resistant cellulosic fiber thermal insulation material from a fibrous web of unrefined virgin softwood and hardwood provides fibers which provides an R-value (as measured by the ASTM C518 test) of at least about 3, and a wood ash fire retardant component present in and/or on the fibrous web in an amount of at least about 1.5% by weight of the fibrous web and sufficient to impart at least partial fire resistance (as measured by the ASTM E970-08A test) to the fibrous web. Also, a process for preparing this at least partially fire resistant thermal insulation material.

FIELD OF THE INVENTION

The present invention broadly relates to an at least partially fireresistant cellulosic fiber insulation material comprising unrefinedvirgin softwood and hardwood wood pulp fibers in a fibrous web, and awood ash fire retardant component present in an amount of at least 1.5%by weight (based on the fibrous web) in and/or on the fibrous web andsufficient to impart at least partial fire resistance to the fibrousweb. The present invention also broadly relates to a process forpreparing this at least partially fire resistant insulation material.

BACKGROUND

Thermal insulation is used in many building structures including homes,offices, etc. Thermal insulation may provide energy efficiencies in thebuilding, more uniform temperatures throughout the building space,minimal recurring expense, etc. In, for example, home insulation, theeffectiveness of thermal insulation is commonly evaluated by its R-valuewhich is a measure of thermal resistance of the insulation (“heat lossretardation”) under specified test conditions. Generally, the higher theR-value is, the more effective is the material as a thermal insulator orbarrier. In addition to its thermal barrier properties, thermalinsulation may provide other benefits such as, for example, absorbingnoise or vibrations (i.e., also provides acoustical insulation), fireresistance, etc.

Thermal insulation may be prepared from a variety materials which reducethe rate of heat transfer. These materials may include glass fibers(fiberglass), polystyrene, polyurethane foam, vermiculite, cellulosicfibers (e.g., wood fibers, cotton fibers, etc.), etc. For example,thermal insulation may be prepared from fiberglass in the form ofpre-cut batts, blankets formed from continuous rolls, etc. Potentialdrawbacks of fiberglass insulation is that it may be challenging toinstall in certain building locations, may not be as easy to recycle,may eventually pose environmental issues due to the glass fibers it isformed from, may be more expensive than other insulation materials, etc.

Thermal insulation may also be prepared from polymer foams such asfoamed polystyrene, polyurethane foam, etc. For example, in the case ofpolyurethane foam, a two component mixture may be combined at the tip ofa spray gun, and thus form an expanding foam which is sprayed ontoconcrete slabs, into wall cavities (spaces) of an unfinished wall,against the interior side of wall sheathing, through holes drilled insuch sheathing or drywall into the wall cavity (space) of a finishedwall, etc. Potential drawbacks of such polymer foam insulation arerelatively high cost, may release hazardous fumes when burned, mayinclude environmentally hazardous monomers (e.g., isocyanates), mayshrink during curing, may involve blowing agents that createenvironmental issues (e.g., “greenhouse gases”), etc.

Thermal insulation may also be prepared from cellulosic fibers in theform flexible batts, rigid panels, etc. Batts formed from suchcellulosic fiber insulation may be more difficult to cut. Instead, thecellulosic fiber insulation may be in the form of a loose fill material.In the case of loose fill materials, this cellulosic fiber insulationoften comprises wood fibers derived from recycled paper (e.g.,newspaper).

This loose-fill cellulosic fiber insulation may be blown, pumped, etc.,into spaces, cavities, etc., (e.g., in to attic areas, into cavities,spaces, etc., in walls, etc.) into the building structure duringinstallation. Potential drawbacks of such loose-fill insulationmaterials include settling over time, thus decreasing its thermalinsulation value, lack of fire resistance unless fire retardantmaterials are incorporated, etc. Also, such blown in loose-fillcellulosic fiber insulation primarily depends upon reliable sources ofrecycled paper to be cost effective. As more and more businesses andhomes go “paperless,” such sources of recycled paper for such blown inloose-fill cellulosic fiber insulation may eventually be on the decline.

SUMMARY

According to a first broad aspect of the present invention, there isprovided an article comprising an at least partially fire resistantcellulosic fiber thermal insulation material comprising:

-   -   a fibrous web providing an R-value (as measured by the ASTM C518        test) of at least about 3 and comprising:        -   from about 5 to about 85% unrefined virgin softwood pulp            fibers by weight of the fibrous web; and        -   from about 15 to about 95% unrefined virgin hardwood pulp            fibers by weight of the fibrous web; and        -   at least about 1.5% by weight of the fibrous web of a wood            ash fire retardant component in and/or on the fibrous web            and sufficient to impart at least partial fire resistance            (as measured by the ASTM E970-08A test) to the fibrous web.

According to a second broad aspect of the present invention, there isprovided a process comprising the following steps:

-   -   a. providing a fibrous web providing an R-value (as measured by        the ASTM C518 test) of at least about 3 and comprising:        -   from about 5 to about 85% unrefined virgin softwood pulp            fibers by weight of the fibrous web; and        -   from about 15 to about 95% unrefined virgin hardwood pulp            fibers by weight of the fibrous web; and    -   b. treating the fibrous web with a wood ash fire composition        comprising a wood ash fire retardant component such that wood        ash fire retardant component is present in and/or on the fibrous        web in an amount of at least about 1.5%, by weight of the        fibrous web and sufficient to provide a cellulosic fiber thermal        insulation material which is at least partially fire resistant        (as measured by the ASTM E970-08A test).

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in conjunction with the accompanyingdrawings, in which:

The FIG. 1 is a schematic diagram which shows an illustrative processfor providing at least partially fire resistant thermal cellulosic fiberinsulation material according to an embodiment of the present invention;

FIG. 2 a schematic diagram illustrating an embodiment of a process fortreating one or both surfaces of a fibrous web with a wood ash fireretardant composition using a metering rod size press;

FIG. 3 a schematic diagram illustrating an embodiment of a process fortreating one or both surfaces of a fibrous web with a wood ash fireretardant using a horizontal flooded nip size press; and

FIG. 4 a schematic diagram illustrating an embodiment of a process fortreating one or both surfaces of a fibrous web with a wood ash fireretardant using a vertical flooded nip size press; and

DETAILED DESCRIPTION

It is advantageous to define several terms before describing theinvention. It should be appreciated that the following definitions areused throughout this application.

Definitions

Where the definition of terms departs from the commonly used meaning ofthe term, applicant intends to utilize the definitions provided below,unless specifically indicated.

For the purposes of the present invention, directional terms such as“top,” “bottom,” “side,” “front,” “frontal,” “forward,” “rear,”“rearward,” “back,” “trailing,” “above,” “below,” “left,” “right,”“horizontal,” “vertical,” “upward,” “downward,” etc., are merely usedfor convenience in describing the various embodiments of the presentinvention. The embodiments shown in FIGS. 1 through 4 may be flippedover, rotated by 90° in any direction, etc.

For the purposes of the present invention, the term “thermal insulation”refers to materials which reduce the rate of heat transfer.

For the purposes of the present invention, the term “R-value” refers tothe conventional measure of thermal resistance (thermal insulation) usedin the building and construction industry. Under uniform conditions, theR-value measures the ratio of the thermal temperature difference acrossan insulating material and the heat flux through it (i.e., is a measureof the insulating material's heat loss retardation). Generally, thehigher the R-value of the material, the more effective the materialfunctions as an insulator. R-values may be given in terms of m²° K/W, orthe equivalent in terms of m²° C./W (International System of Units), orft²° Fh/BTU (United States customary units). For purposes of the presentinvention, the R-value is measured according to test method ASTM C518(Standard Test Method for Steady-State Thermal Transmission Propertiesby Means of a Heat Flow Meter Apparatus) which provides values in termsof United States customary units.

For the purposes of the present invention, the term “fibrous web” refersto a fibrous cellulosic matrix comprising at least unrefined virginsoftwood fibers and unrefined virgin hardwood fibers. The fibrous webmay be in the form of, for example, sheets, strips, pieces,batts/battings, blankets, etc., which may be in the form of a continuousroll, a discrete sheet, etc.

For the purposes of the present invention, the term “virgin pulp fibers”refers to wood pulp fibers which are derived from pulp obtained directlyfrom wood sources (e.g., trees), and which are not derived from recycledsources, such as recycled paper.

For the purposes of the present invention, the terms “batt,” “batting,”and “blanket” refer interchangeably herein to a piece, sheet, strip,etc., of thermal insulation material.

For the purposes of the present invention, the term “softwood pulpfibers” refers to fibrous pulps (pulp fibers) derived from the woodysubstance of coniferous trees (gymnosperms) such as varieties of fir,spruce, pine, etc., for example, loblolly pine, slash pine, Coloradospruce, balsam fir, Douglas fir, jack pine, radiata pine, white spruce,lodgepole pine, redwood, etc. North American southern softwoods andnorthern softwoods may be used to provide softwood pulp-fibers, as wellas softwoods from other regions of the world.

For the purposes of the present invention, the term “hardwood pulpfibers” refers to fibrous pulps (pulp fibers) derived from the woodysubstance of deciduous trees (angiosperms) such as birch, oak, beech,maple, eucalyptus, poplars, etc.

For the purposes of the present invention, the term “unrefined pulpfibers” refers to wood pulp fibers which have not been refined, i.e.,have not be subjected to a process of mechanical treatment, such asbeating, to develop or modify the pulp fibers, often to increase fiberbonding strength and/or improve surface properties. See G. A. Smook,Handbook for Pulp and Paper Technologists (2^(nd) Edition, 1992), page191-202, the entire contents and disclosure of which is hereinincorporated by reference, for a general description of the refining ofpulp fibers.

For the purposes of the present invention, the term “basis weight,”refers to the grammage of the wood pulp fibers, fibrous web, etc., asdetermined by TAPPI test T410. See G. A. Smook, Handbook for Pulp andPaper Technologists (2^(nd) Edition, 1992), page 342, Table 22-11, theentire contents and disclosure of which is herein incorporated byreference, which describes the physical test for measuring basis weight.

For the purposes of the present invention, the term “moisture content,”refers to the amount of water present in the fibrous web as measured byTAPPI test T210 cm-03.

For the purposes of the present invention, the term “pulp filler” referscommonly to mineral products (e.g., calcium carbonate, kaolin clay,calcium sulfate hemihydrate, calcium sulfate dehydrate, chalk, etc.)which may be used in fibrous pulp making to reduce materials cost perunit mass of the fibrous web, increase opacity, etc. These mineralproducts may be finely divided, for example, in the size range of fromabout 0.5 to about 5 microns.

For the purposes of the present invention, the term “pulp pigment”refers to a material (e.g., a finely divided particulate matter) whichmay be used or may be intended to be used to affect optical propertiesof fibrous web, etc. Pulp pigments may include one or more of: calciumcarbonate, kaolin clay, calcined clay, modified calcined clay, aluminumtrihydrate, titanium dioxide, talc, plastic pigment, amorphous silica,aluminum silicate, zeolite, aluminum oxide, colloidal silica, colloidalalumina slurry, etc.

For the purposes of the present invention, the term “calcium carbonate”refers various calcium carbonates which may be used as pulp pigments,such as precipitated calcium carbonate (PCC), ground calcium carbonate(GCC), modified PCC and/or GCC, etc.

For the purposes of the present invention, the term “precipitatedcalcium carbonate (PCC)” refers to a calcium carbonate which may bemanufactured by a precipitation reaction and which may used as a pulppigment. PCC may comprise almost entirely of the calcite crystal form ofCaCO₃. The calcite crystal may have several different macroscopic shapesdepending on the conditions of production. Precipitated calciumcarbonates may be prepared by the carbonation, with carbon dioxide (CO₂)gas, of an aqueous slurry of calcium hydroxide (“milk of lime”). Thestarting material for obtaining PCC may comprise limestone, but may alsobe calcined (i.e., heated to drive off CO₂), thus producing burnt lime,CaO. Water may added to “slake” the lime, with the resulting “milk oflime,” a suspension of Ca(OH)₂, being then exposed to bubbles of CO₂gas. Cool temperatures during addition of the CO₂ tend to producerhombohedral (blocky) PCC particles. Warmer temperatures during additionof the CO₂ tend to produce scalenohedral (rosette-shaped) PCC particles.In either case, the end the reaction occurs at an optimum pH where themilk of lime has been effectively converted to CaCO₃, and before theconcentration of CO₂ becomes high enough to acidify the suspension andcause some of it to redissolve. In cases where the PCC is notcontinuously agitated or stored for many days, it may be necessary toadd more than a trace of such anionic dispersants as polyphosphates. WetPCC may have a weak cationic colloidal charge. By contrast, dried PCCmay be similar to most ground CaCO₃ products in having a negativecharge, depending on whether dispersants have been used. The calciumcarbonate may be precipitated from an aqueous solution in threedifferent crystal forms: the vaterite form which is thermodynamicallyunstable, the calcite form which is the most stable and the mostabundant in nature, and the aragonite form which is metastable undernormal ambient conditions of temperature and pressure, but which mayconvert to calcite at elevated temperatures. The aragonite form has anorthorhombic shape that crystallizes as long, thin needles that may beeither aggregated or unaggregated. The calcite form may exist in severaldifferent shapes of which the most commonly found are the rhombohedralshape having crystals that may be either aggregated or unaggregated andthe scalenohedral shape having crystals that are generally unaggregated.

For the purposes of the present invention, the term “comminuting” refersto defibrizing, disintegrating, shredding, fragmenting, etc., thefibrous web to provide a loose fiber mixture (e.g., for loose-fillcellulose insulation).

For the purposes of the present invention, the term “loose-fillcellulose insulation” refers to a loose, generally free-flowing, fibermixture formed by comminuting a fibrous mixture which may be used inproviding, for example, blown-in cellulose insulation.

For the purposes of the present invention, the term “trivalent metal”refers to a metal which may have a positive charge of three (e.g.,boron, zinc, an iron (ferric), cobalt, nickel, aluminum, manganese,chromium, etc.), and may include combinations of one or more of thesetrivalent metals. Sources of trivalent metals may include one or more oforganic or inorganic salts, for example, from one or more of thefollowing anions: acetate, lactate, EDTA, halide, chloride, bromide,nitrate, chlorate, perchlorate, sulfate, acetate, carboxylate,hydroxide, nitrite, etc. The salt may be a simple salt, wherein thetrivalent metal forms a salt with one or more of the same anion, or acomplex salt, wherein the trivalent metal forms a salt with two or moredifferent anions. In some embodiments, the salt may be aluminumchloride, aluminum carbonate, aluminum sulfate, alum (e.g., aluminumammonium sulfate, aluminum potassium sulfate, aluminum sulfate, etc.),etc.

For the purposes of the present invention, the term “debondersurfactant” refers to surfactants which are useful in the treatment ofwood pulp fibers to reduce inter-fiber bonding. Suitable debondersurfactants may include one or more of: cationic surfactants or nonionicsurfactants, such as linear or branched monoalkyl amines, linear orbranched dialkyl amines, linear or branched tertiary alkyl amines,linear or branched quaternary alkyl amines, linear or branched,saturated or unsaturated hydrocarbon surfactants, fatty acid amides,fatty acid amide quaternary ammonium salts, dialkyl dimethyl quaternaryammonium salts, dialkylimidazolinium quaternary ammonium salts, dialkylester quaternary ammonium salts, triethanolamine-ditallow fatty acids,fatty acid ester of ethoxylated primary amines, ethoxylated quaternaryammonium salts, dialkyl amide of fatty acids, dialkyl amide of fattyacids, ethoxylated alcohols, such as C₁₆-C₁₈ unsaturated alkyl alcoholethoxylates, commercially available compound having CAS Registry No.68155-01-1, commercially available compound having CAS Registry No.26316-40-5, commercially available Eka Chemical F60™ (an ethoxylatedalcohol surfactant), commercially available Cartaflex TS LIQ™,commercially available F639™, commercially available Hercules PS9456™,commercially available Cellulose Solutions 840™, commercially availableCellulose Solutions 1009™, commercially available EKA 509H™,commercially available EKA 639™, etc. See also U.S. Pat. No. 4,425,186(May et al.), issued Jan. 10, 1984, the entire contents and disclosureof which is hereby incorporated by reference, which discloses acombination of a cationic surfactant and a dimethylamide of a straightchain carbon carboxylic acid containing 12 to 18 carbon atoms which maybe useful as a debonder surfactant.

For the purposes of the present invention, the term “fire resistance”refers to the ability of a material (e.g., a fibrous web, etc.) to beresistant to fire, flame, burning, etc., as determined by certain fireresistance test(s), such as the ASTM E970-08A test, etc.

For the purposes of the present invention, the term “fire resistancetest” refers to a test which measures the fire resistantcharacteristics, properties, etc., of an article, a material, etc. Forthe purposes of the present invention, fire resistance is measured interms of test method ASTM E970-08A (Standard Test Method for CriticalRadiant Flux of Exposed Attic Floor Insulation Using a Radiant HeatEnergy Source).

For the purposes of the present invention, the term “partially fireresistant” refers to a material (e.g., a fibrous web, etc.) which hasbeen treated with sufficient fire retardant such that the treatedmaterial has at least some measurable increase in fire resistance, asdetermined by the ASTM E970-08A test, relative to the untreatedmaterial. A treated material which passes the ASTM E970-08A test isreferred to herein as being “significantly fire resistant.”

For the purposes of the present invention, the term “fire retardant”refers to one or more substances (e.g., composition, compound, etc.)which are able to reduce, impart resistance to, etc., the flammability,the ability to burn, etc., of a material, article, etc. Fire retardantsmay include one or more of: wood ash fire retardants, fire retardantsother than wood ash fire retardants, such as borate fire retardants,phosphorous fire retardants, halogenated hydrocarbon fire retardants,metal oxide fire retardants, etc. For example, the fire retardant maycomprise a mixture, blend, etc., of one or more wood ash fireretardants, one or more borate fire retardants, one or more phosphorousfire retardants, one or more halogenated hydrocarbon fire retardants,and one or more metal oxide fire retardants.

For the purposes of the present invention, the “wood ash fire retardant”refers to a fire retardant composition comprising the components of woodash. Wood ash is the residue remaining after the combustion (burning) ofwood. Wood ash may comprise, for example, between about 0.43% and about1.82% of the mass (solids basis) of burned wood. A major component ofwood ash obtained from burned wood is calcium carbonate. Wood ash mayalso comprise other components such as potash (potassium salts), such aspotash alum (potassium aluminum sulfate), phosphates, sodium carbonate,clays, talc, etc., as well as trace quantities of iron, manganese, zinc,copper, heavy metals, etc. The wood ash fire retardant used inembodiments of the present invention may be derived directly from woodash or may be formed from the components present in wood ash. Someillustrative embodiments of wood ash fire retardant components hereinmay comprise, for example, one or more of: calcium carbonate; potashalum (potassium aluminum sulfate); sodium carbonate; clay; talc; etc.

For the purposes of the present invention, the term “borate fireretardant” refers to a fire retardant substance, compound, molecule,etc., which comprises one or more boron atoms. Borate fire retardantsmay include one or more of: boric acid, borax, sodium tetraboratedecahydrate, borosilicates (e.g., sodium borosilicates, potassiumborosilicates, etc.), etc.)

For the purposes of the present invention, the term “phosphorous fireretardant” refers to a fire retardant substance, compound, molecule,etc., which comprises one or more phosphorous atoms. Phosphorous fireretardants may include one or more of: phosphates, such as sodiumphosphates, ammonium phosphates, sodium polyphosphates, ammoniumpolyphosphates, melamine phosphates, ethylenediamine phosphates etc.;red phosphorus; metal hypophosphites, such as aluminum hypophosphite andcalcium hypophosphite; phosphate esters; etc. Some proprietaryphosphorous fire retardants may include, for example: Spartan™ AR 295Flame Retardant from Spartan Flame Retardants Inc. of Crystal Lake,Ill., include both organic and inorganic constituents, GLO-TARD FFR2,which is an ammonium polyphosphate fire retardant from GLO-TEXInternational, Inc. of Spartanburg, S.C.; Fire Retard 3496, which is aphosphate ester supplied by Manufacturers Chemicals, L. P. of Cleveland,Term, Flovan CGN, a multi-purpose phosphate-based flame retardantsupplied by Huntsman (Salt Lake City, Utah); SPARTAN™ AR 295, adiammonium phosphate based flame retardant from Spartan FlameRetardants, Inc. (Crystal Lake, Ill.), FRP 12™, FR 165™, and FR 8500™supplied by Cellulose Solutions, LLC (Daphne, Ala.), etc.

For the purposes of the present invention, the term “halogenated organicfire retardant” refers to a halogenated organic compound which alone, orin combination with other substances, compounds, molecules, etc., arecapable of functioning as a fire retardant. Halogenated organic fireretardants may include one or more of: halogenated (e.g., chlorinated,brominated, etc.) hydrocarbons, such as halogenated aliphatics (e.g.,haloalkanes), halogenated aromatics, etc. Halogenated organic fireretardants may include chloroparaffins, Dechorane Plus (achlorine-containing halogenated fire retardant), decabromodiphenyloxide, tetradecabromodiphenoxybenzene, ethylenebispentabromobenzene(EBPB); tetrabromobisphenol A (TBBA), tetrabromobisphenol Abis-hexabromocyclododecane, ethylenebis-(tetrabromophthalimide). Thesehalogenated organic fire retardants may work by eliminating oxygen fromthe burn zone which quenches, extinguishes, smothers, puts out, etc.,the flame.

For the purposes of the present invention, the term “metal oxide fireretardant” refers to metal oxides which alone, or in combination withother substances, are capable of functioning as a fire retardant. Metaloxide fire retardants may include one or more of: aluminum oxide(alumina), antimony trioxide, ferric oxide, titanium dioxide, stannicoxide, etc.

For the purposes of the present invention, the term “solids basis”refers to the weight percentage of each of the respective solidmaterials, compounds, substances, etc., (e.g., pulp fibers, fireretardants, surfactants, etc.) present in the pulp slurry, furnish,fibrous web, composition, etc., in the absence of any liquids (e.g.,water). Unless otherwise specified, all percentages given herein for thesolid materials, compounds, substances, etc., are on a solids basis.

For the purposes of the present invention, the term “solids content”refers to the percentage of non-volatile, non-liquid components (byweight) that are present in the composition, etc.

For the purposes of the present invention, the term “gsm” is used in theconventional sense of referring to grams per square meter.

For the purposes of the present invention, the term “liquid” refers to anon-gaseous fluid composition, compound, material, etc., which may bereadily flowable at the temperature of use (e.g., room temperature) withlittle or no tendency to disperse and with a relatively highcompressibility.

For the purposes of the present invention, the term “room temperature”refers to the commonly accepted meaning of room temperature, i.e., anambient temperature of 20° to 25° C.

For the purposes of the present invention, the term “optical brightness”refers to the diffuse reflectivity of the pulp web/fibers, for example,at a mean wavelength of light of 457 nm. As used herein, opticalbrightness of pulp webs may be measured in terms of ISO Brightness whichmeasures brightness using, for example, an ELREPHO Datacolor 450spectrophotometer, according to test method ISO 2470-1, using a Cilluminant with UV included.

For the purposes of the present invention, the term “optical brighteneragent (OBA)” refers to certain fluorescent materials which may increasethe brightness (e.g., white appearance) of pulp web surfaces byabsorbing the invisible portion of the light spectrum (e.g., from about340 to about 370 nm) and converting this energy into thelonger-wavelength visible portion of the light spectrum (e.g., fromabout 420 to about 470 nm). In other words, the OBA converts invisibleultraviolet light and re-emits that converted light into blue toblue-violet light region through fluorescence. OBAs may also be referredto interchangeably as fluorescent whitening agents (FWAs) or fluorescentbrightening agents (FBAs). The use of OBAs is often for the purpose ofcompensating for a yellow tint or cast of paper pulps which have, forexample, been bleached to moderate levels. This yellow tint or cast isproduced by the absorption of short-wavelength light (violet-to-blue) bythe pulp webs. With the use of OBAs, this short-wavelength light thatcauses the yellow tint or cast is partially replaced, thus improving thebrightness and whiteness of the pulp web. OBAs are desirably opticallycolorless when present on the pulp web surface, and do not absorb lightin the visible part of the spectrum. These OBAs may be anionic,cationic, anionic (neutral), etc., and may include one or more of:stilbenes, such as 4,4′-bis-(triazinylamino)-stilbene-2,2′-disulfonicacids, 4,4′-bis-(triazol-2-yl)stilbene-2,2′-disulfonic acids,4,4′-dibenzofuranyl-biphenyls, 4,4′-(diphenyl)-stilbenes,4,4′-distyryl-biphenyls, 4-phenyl-4′-benzoxazolyl-stilbenes,stilbenzyl-naphthotriazoles, 4-styryl-stilbenes, bis-(benzoxazol-2-yl)derivatives, bis-(benzimidazol-2-yl) derivatives, coumarins,pyrazolines, naphthalimides, triazinyl-pyrenes, 2-styryl-benzoxazole or-naphthoxazoles, benzimidazole-benzofurans or oxanilides, etc, Seecommonly assigned U.S. Pat. No. 7,381,300 (Skaggs et al.), issued Jun.3, 2008, the entire contents and disclosure of which is hereinincorporated by reference. In particular, these OBAs may comprise, forexample, one or more stilbene-based sulfonates (e.g., disulfonates,tetrasulfonates, or hexasulfonates) which may comprise one or twostilbene residues. Illustrative examples of such anionic stilbene-basedsulfonates may include 1,3,5-triazinyl derivatives of4,4′-diaminostilbene-2,2′-disulphonic acid (including salts thereof),and in particular the bistriazinyl derivatives (e.g.,4,4-bis(triazine-2-ylamino)stilbene-2,2′-disulphonic acid), the disodiumsalt of distyrlbiphenyl disulfonic acid, the disodium salt of4,4′-di-triazinylamino-2,2′-di-sulfostilbene, etc. Commerciallyavailable disulfonate, tetrasulfonate and hexasulfonate stilbene-basedOBAs may also be obtained, for example, from Ciba Geigy under thetrademark TINOPAL®, from Clariant under the trademark LEUCOPHOR®, fromLanxess under the trademark BLANKOPHOR®, and from 3V under the trademarkOPTIBLANC®.

For the purpose of the present invention, the term “treating” withreference to the fire retardant compositions may include adding,depositing, applying, spraying, coating, daubing, spreading, wiping,dabbing, dipping, etc.

For the purposes of the present invention, the term “applicator” refersto a device, equipment, machine, etc., which may be used to treat,apply, coat, etc., one or more sides or surfaces of a fibrous web withthe fire retardant composition. Applicators may include air-knifecoaters, rod coaters, blade coaters, size presses, etc. See G. A. Smook,Handbook for Pulp and Paper Technologists (2^(nd) Edition, 1992), pages289-92, the entire contents and disclosure of which is hereinincorporated by reference, for a general description of coaters that maybe useful herein. Size presses may include a puddle size press, ametering size press, etc. See G. A. Smook, Handbook for Pulp and PaperTechnologists (2^(nd) Edition, 1992), pages 283-85, the entire contentsand disclosure of which is herein incorporated by reference, for ageneral description of size presses that may be useful herein.

For the purposes of the present invention, the term “flooded nip sizepress” refers to a size press having a flooded nip (pond), also referredto as a “puddle size press.” Flooded nip size presses may includevertical size presses, horizontal size presses, etc.

For the purposes of the present invention, the term “metering sizepress” refers to a size press that includes a component for spreading,metering, etc., deposited, applied, etc., the fire retardant compositionon a fibrous web. Metering size presses may include a rod metering sizepress, a gated roll metering size press, a doctor blade metering sizepress, etc.

For the purposes of the present invention, the term “rod metering sizepress” refers to metering size press that uses a rod to spread, meter,etc., the fire retardant composition on a pulp web, air-laid fibrousstructure, etc. The rod may be stationary or movable relative to theweb.

For the purposes of the present invention, the term “gated roll meteringsize press” refers to a metering size press that may use a gated roll,transfer roll, soft applicator roll, etc. The gated roll, transfer roll,soft applicator roll, etc., may be stationery relative to the web, mayrotate relative to the web, etc.

For the purposes of the present invention, the term “doctor blademetering size press” refers to a metering press which may use a doctorblade to spread, meter, etc., the fire retardant composition on afibrous web.

For the purposes of the present invention, the term “disc refiner”refers to a device comprising a rotating disc-stator assembly which maybe used for comminuting (e.g., defibrizing, disintegrating, shredding,fragmenting, etc.) fibrous materials into a loose-fill material for usein, for example, blown-in insulation. See G. A. Smook, Handbook for Pulpand Paper Technologists (2^(nd) Edition, 1992), page 196-201, the entirecontents and disclosure of which is herein incorporated by reference,for a general description of disc refiners. Illustrative disc refinerssuitable for use in comminuting (e.g., defibrizing, disintegrating,shredding, fragmenting, etc.) fibrous materials into a loose-fillmaterial for suitable use in blown-in insulation include those disclosedin, for example, U.S. Pat. No. 5,011,091 (Kopecky), issued Apr. 30,1991; U.S. Pat. No. 2,982,482 (Curtis), issued; U.S. Pat. No. 3,049,307(Dalzell), issued Aug. 14, 1962; U.S. Pat. No. 2,654,295 (Sutherland),issued Oct. 6, 1953; U.S. Pat. No. 3,815,834 (Gilbert), issued Jun. 11,1974, the entire contents and disclosures of which are hereinincorporated by reference.

DESCRIPTION

Embodiments of the at least partially fire resistant cellulosic fiberthermal insulation material of the present invention may comprise afibrous web comprising from about 5 to about 85% (for example, fromabout 10 to about 60%, such as from about 15 to about 30%) unrefinedvirgin softwood pulp fibers (by weight of the fibrous web); and fromabout 15 to about 95% (for example, from about 40 to about 90%, such asfrom about 70 to about 85%) unrefined virgin hardwood fibers (by weightof the fibrous web); and at least about 1.5% by weight of the fibrousweb of a wood ash fire retardant component in and/or on the fibrous web,for example, from about 1.5 to about 20% by weight (based on the fibrousweb), such as from about 1.5 to about 5% weight (based on the fibrousweb), and sufficient to impart at least partial fire resistance (asmeasured by the ASTM E970-08A test) to the fibrous web. Amounts of thewood ash fire retardant component above about 20% by weight (based onthe fibrous web) are usable in embodiments of the present invention, butmay also provide a sufficient amount of fine particles to causeexcessive dustiness in the at least partially fire resistant cellulosicfiber thermal insulation material.

The fibrous web provides an R-value of at least about 3 (as measured bythe ASTM C518 test), for example, R-values in the range of from about 3to about 4.5, such as from about 3.4 to about 4.2. The fibrous web mayhave a basis weight about 850 gsm or less (for example, about 500 gsm orless). The fibrous web may also have a moisture content of less thanabout 20% (for example, about 12% or less). The fibrous web may furtherinclude one or more debonder surfactants in an amount (based on thefibrous web) of, for example, from about 0.05 to about 0.35% by weight,such as from about 0.075 to about 0.15% by weight. Including one or moredebonder surfactants may lower the amount of energy which may berequired to in comminuting (e.g., defibrizing, disintegrating,shredding, fragmenting, etc.) the fire resistant cellulosic fiberthermal insulation material with, for example, a disc refiner to providea loose-fill blown-in insulation material. Lower the energy required incomminuting (e.g., defibrizing, disintegrating, shredding, fragmenting,etc.) the fire resistant cellulosic fiber thermal insulation materialmay provide a beneficial decrease in the amount of dust generated.Inclusion of one or more debonder surfactants may also enhance theanti-mold properties of embodiments of the fire resistant cellulosicfiber thermal insulation material, as well as increase the bulk of thematerial (e.g., meaning less material may be required per bag, package,etc., that the material is distributed in).

Embodiments of the process of the present invention for providing fireresistant fibrous webs may comprise the following steps: (1) providing afibrous web providing an R-value (as described above) comprisingunrefined virgin softwood and hardwood pulp fibers (in amounts asdescribed above); and (2) treating the fibrous web with wood ash fireretardant composition comprising wood ash fire retardant component suchthat the wood ash fire retardant component is present in and/or on thefibrous web in an amount of at least about 1.5%, by weight of thefibrous web and sufficient to provide a cellulosic fiber thermalinsulation material which is at least partially fire resistant (asmeasured by the ASTM E970-08A test).

In treating the fibrous web with the wood ash fire retardantcomposition, the wood ash fire retardant composition may be provide as asolid granular or powered mixture, as a slurry have, for example, apaste-like consistency, as a liquid dispersion, as a liquid solution,etc. The fibrous web may be treated with the wood ash fire retardantcomposition in a variety places during the making of the fire resistantthermal insulation material. For example, the wood retardant fireretardant composition may be applied by a papermaking size press, apaper coater, a sprayer, a dispenser, a douser, etc. The incorporation,addition, etc., of one or more trivalent metal cations (e.g., aluminumsuch as in the form of, for example, alum as the source) in and/or onthe fibrous web (e.g., in the blend chest or in the pulp slurry at leastprior to the headbox which deposits the fibrous furnish on the formingwire) prior to treatment with the wood ash fire retardant composition,with or without debonder surfactant, may also enable the fire retardantcomposition to be distributed and dispersed more thoroughly,homogeneously, etc., and may also aid, assist, etc., in having the fireretardants crosslink, bond, cure, etc., more effectively to thecellulosic fibers in the fibrous web.

In some embodiments of the at least partially fire resistant cellulosicfiber insulation material, the fibrous web may be treated with a fireretardant component which comprises a mixture, blend, etc., of one ormore wood ash fire retardants, along with one or more of these otherfire retardants, for example, to provide a significantly fire resistantcellulosic fiber insulation material, i.e., passes the ASTM E970-08Atest. For example, the fibrous web may also be treated with one or moreborate fire retardants, phosphorous fire retardants, halogenatedhydrocarbon fire retardants, metal oxide fire retardants, etc. Thefibrous web may be treated with these one or more other fire retardantsin amounts sufficient to render the cellulosic fiber insulation materialsignificantly fire resistant, i.e., sufficient to pass the ASTM E970-08Atest. For example, these other fire retardants may be added in amountsof from about 15 to about 25% by weight (based on the fibrous web), suchas from about 15 to about 18% by weight.

Embodiments of the at least partially fire resistant cellulosic fiberthermal insulation material of the present invention may be provided inthe form of sheets, pieces, rolls, etc. The fire resistant cellulosicfiber thermal insulation material may be comminuted (e.g., defiberized,disintegrated, shredded, fragmented, etc.) to provide loose-fillcellulose insulation using known methods. For example, the at leastpartially fire resistant cellulosic fiber thermal insulation materialmay be defiberized, disintegrated, shredded, fragmented, etc., by usinga disc refiner. The resultant at least partially fire resistantloose-fill cellulose insulation may then be used to provide blown-incellulose insulation in various building structures including homes,offices, etc.

Embodiments the process of the present invention for providing at leastpartially fire resistant cellulosic fiber thermal insulation materialare further illustrated in FIG. 1. FIG. 1 is a schematic diagram whichshows an illustrative process for providing an at least partially fireresistant thermal cellulosic fiber insulation material according to anembodiment of the present invention, which is indicated generally as100. In process 100, unrefined virgin softwood pulp fibers (indicated asSoftwood Fibers 102) and unrefined virgin hardwood pulp fibers(indicated as Hardwood Fibers 104) may be combined, blended together,etc., as indicated by respective arrows 106 and 108 in a Blend Chest,indicated generally as 110. For example, in one embodiment, SoftwoodFibers 102 and Hardwood Fibers 104 may be mixed in Blend Chest 110(together with any other optional additives such as pulp pigments,mixing/web penetration aids, debonder surfactants, etc.). As indicatedby arrow 112, Blend Chest 110 provides a pulp mixture in the form ofPulp Slurry 114. As indicated by arrow 116, the wood ash fire retardantcomponent (see Wood Ash 118) may be added to Pulp Slurry 114. Asindicated by arrow 120, a source of trivalent metal ions, such as Alum122, may also be added to Pulp Slurry 114. (Added Alum 122 may alsoprovide some additional benefit as a fire retardant.)

As further shown in FIG. 1, after adding Wood Ash 116 and Alum 122 andas indicated by arrow 1124, Pulp Slurry 114 by may then be deposited(e.g., by using a headbox) as a furnish of wood pulp fibers, onto aforming wire, forming table, forming screen, forming fabric, etc., suchas a Fourdrinier forming wire (see Forming Wire 126) to provide afibrous web. As indicated by arrow 128, the fibrous web on Forming Wire126 may also be optionally treated with Debonder Surfactant 130 byusing, for example, a spray boom, to apply (spray) on DebonderSurfactant 130 on the fibrous web. The fibrous web on Forming Wire 126(with or without Debonder Surfactant 130) may then be transferred, asindicated by arrow 132, to a Dryer 134, to provide a dried fibrous web.As indicated by arrow 136, the dried web from Dryer 134 provides a fireresistant cellulosic fiber thermal insulation material (see InsulationMaterial 138) which may be in the form of, for example, sheets, rolls,etc.

An alternative embodiment of process 100 is also shown in FIG. 1. Inthis alternative embodiment of process 100, Wood Ash 118 added to PulpSlurry 114 provides only a portion of the total wood ash fire retardantcomponent (e.g., from about 5 to 100%, such as from about 10 to about90%, of the total wood ash fire retardant component) present in and/orthrough the fibrous web. Instead, the fibrous web from Forming Wire 126passes through, as indicated by arrow 140, a Size Press, indicatedgenerally as 142. At Size Press 142, the fibrous web may be treated, asindicated by arrow 144, with the remaining wood ash fire retardantcomponent (e.g., from 0 to about 95%, such as from about 10 to about90%, of the total wood ash fire retardant component), indicated as WoodAsh 146. (See, for example, FIGS. 2-4 and corresponding descriptionbelow, for treating the fibrous web with the remaining portion of WoodAsh 146 using a Size Press 142.) As also shown in FIG. 1, the fibrousweb may optionally be treated at Size Press 142, as indicated by arrow148, with Other Fire Retardants 150, such as borate fire retardants,phosphorous fire retardants, halogenated hydrocarbon fire retardants,metal oxide fire retardants, etc. (In an alternative embodiment, insteadof using Size Press 142, the fibrous web may be treated with theremaining Wood Ash 146 and/or Other Fire Retardants 150 by using, forexample, a spray boom, to apply (spray) Wood Ash 146 and/or Other FireRetardants 150 on the fibrous web.) After being treated with remainingWood Ash 146 and/or Other Fire Retardants 150, the additionally treatedfibrous web leaves Size Press 142, as indicated by arrow 152, and isthen dried by Dryer 134.

An embodiment of a process of the present invention for treating one orboth surfaces of fibrous web with a fire retardant wood ash composition(e.g., such as the remaining portion of Wood Ash 146, as well asoptional Other Fire Retardants 150) is further illustrated in FIG. 2.Referring to FIG. 2, an embodiment of a system for carrying out anembodiment of the process of the present invention is illustrated whichmay be in the form of, for example a rod metering size press indicatedgenerally as 200. Size press 200 may be used to coat a fibrous web,indicated generally as 204. Web 204 moves in the direction indicated byarrow 206, and which has a pair of opposed sides or surfaces, indicated,respectively, as 208 and 212.

Size press 200 includes a first assembly, indicated generally as 214,for applying the wood ash fire retardant composition to surface 208.Assembly 214 includes a first reservoir, indicated generally as 216,provided with a supply of a fire retardant composition, indicatedgenerally as 220. A first take up roll, indicated generally as 224 whichmay rotate in a counterclockwise direction, as indicated by curved arrow228, picks up an amount of the fire retardant composition from supply220. This amount of the wood ash fire retardant composition that ispicked up by rotating roll 224 may then be transferred to a firstapplicator roll, indicated generally as 232, which rotates in theopposite and clockwise direction, as indicated by curved arrow 236. (Thepositioning of first take up roll 224 shown in FIG. 2 is simplyillustrative and roll 224 may be positioned in various ways relative tofirst applicator roll 232 such that the wood ash fire retardantcomposition is transferred to the surface of applicator roll 232.) Theamount of the wood ash fire retardant composition that is transferred tofirst applicator roll 232 may be controlled by metering rod 244 whichspreads the transferred composition on the surface of applicator roll232, thus providing relatively uniform and consistent thickness of afirst coating, indicated as 248, when applied onto the first surface 208of web 204 by applicator roll 232.

As shown in FIG. 2, size press 200 may also be provided with a secondassembly indicated generally as 252, for applying the wood ash fireretardant composition to surface 212. Assembly 252 includes a secondreservoir indicated generally as 256, provided with a second supply of awood ash fire retardant composition, indicated generally as 260. Asecond take up roll, indicated generally as 264 which may rotate in aclockwise direction, as indicated by curved arrow 268, picks up anamount of the wood ash fire retardant composition from supply 260. Thisamount of wood ash fire retardant composition that is picked up byrotating roll 264 may then be transferred to second take up roll,indicated generally as 272, which rotates in the opposite andcounterclockwise direction, as indicated by curved arrow 276. Asindicated in FIG. 2 by the dashed-line box and arrow 276, second take uproll 264 may be positioned in various ways relative to second applicatorroll 272 such that the wood ash fire retardant composition istransferred to the surface of applicator roll 272. The amount of woodash fire retardant composition that is transferred to second applicatorroll 272 may be controlled by a second metering rod 284 which spreadsthe transferred composition on the surface of applicator roll 272, thusproviding relatively uniform and consistent thickness of the secondcoating, indicated as 288, when applied onto the second surface 212 ofweb 204 by applicator roll 272.

Referring to FIG. 3, another embodiment of a system for carrying out anembodiment of the process of the present invention is illustrated whichmay be in the form of, for example, a horizontal flooded nip size pressindicated generally as 300. Horizontal size press 300 may be used tocoat a paper web, indicated generally as 304, with a fire retardantcomposition (e.g., as described in FIG. 2 above). Web 304 moves in thedirection indicated by arrow 306, and has a pair of opposed sides orsurfaces, indicated, respectively, as 308 and 312.

Horizontal size press 300 includes a first source of wood ash fireretardant composition, indicated generally as nozzle 316, which issprays a stream of the wood ash fire retardant composition, indicated by320, generally downwardly towards the surface of a first transfer roll,indicated as 332, which rotates in a clockwise direction, as indicatedby curved arrow 336. A flooded pond or puddle, indicated generally as340, is created at the nip between first transfer roll 332 and secondtransfer roll 372 due to a bar or dam (not shown) positioned at belowthe nip. Transfer roll 332 transfers a relatively uniform and consistentthickness of a first coating of the wood ash fire retardant composition,indicated as 348, onto the first surface 308 of web 304.

A second source of fire retardant composition, indicated generally asnozzle 356, which is sprays a stream of the wood ash fire retardantcomposition, indicated by 360, generally downwardly towards the surfaceof a second transfer roll, indicated as 372, which rotates in acounterclockwise direction, as indicated by curved arrow 376. Transferroll 372 transfers a relatively uniform and consistent thickness of asecond coating of the wood ash fire retardant composition, indicated as388, onto the second surface 312 of web 304.

Referring to FIG. 4, another embodiment of a system for carrying out anembodiment of the process of the present invention is illustrated whichmay be in the form of, for example, a vertical flooded nip size pressindicated generally as 400. Vertical size press 400 may be used to coata paper web, indicated generally as 404, with a wood ash fire retardantcomposition (e.g., as described in FIG. 2 above). Web 404 moves in thedirection indicated by arrow 406, and has a pair of opposed sides orsurfaces, indicated, respectively, as 408 and 412.

Vertical size press 400 includes a first source of wood ash fireretardant composition, indicated generally as nozzle 416, which issprays a stream of the fire retardant composition, indicated by 420,generally upwardly and towards the surface of a first lower transferroll of the roll stack, indicated as 432, which rotates in a clockwisedirection, as indicated by curved arrow 436. A smaller flooded pond orpuddle, indicated generally as 440, (compared to the pond or puddle 440of horizontal size press 400) is created at the nip between lower firsttransfer roll 432 and second upper transfer roll 472 due to a bar or dam(not shown) positioned to right of the nip. Transfer roll 432 transfersa relatively uniform and consistent thickness of a first coating of thewood ash fire retardant composition, indicated as 448, onto the lowerfirst surface 408 of web 404.

A second source of wood ash fire retardant composition, indicatedgenerally as nozzle 456, sprays a stream of the wood ash fire retardantcomposition, indicated by 460, generally downwardly and towards thesurface of a second upper transfer roll, indicated as 472, which rotatesin a counterclockwise direction, as indicated by curved arrow 476.Transfer roll 472 transfers a relatively uniform and consistentthickness of a second coating of the wood ash fire retardantcomposition, indicated as 488, onto the upper second surface 412 of web404.

EXAMPLES

The properties, including fire resistance, of various insulation pulpfiber samples (IPFM), are shown in the Table below versus a Controlsample:

Bag Shaken % Weight Density Scan Density Burn Test IPFM Fines¹ (lbs)²(g/g)³ (g/cm³)⁴ (cm)⁵ Control 41.4 28.2 1.58 0.076 36  36% SW 26.4 22.81.29 0.049 120  60% SW 26.8 21.0 1.22 0.051 120  80% SW 26.6 20.5 1.000.048 120 100% HW 35.1 26.0 1.48 0.066 39 100% HSW — — — — 120  50%HSW-WA 37.5 23.0 1.23 0.050 38 100% HSW-WA 26.9 17.5 1.10 0.046 41¹Percentage passing through USA Std #200 screen (75 um hole opening)²Scale weight of 50 ft.² standard cellulose insulation bag ³Measured byASTM C687-07 test ⁴Measured by SCAN-C 33:80 method ⁵Measured as cm ofsample burned (starting sample ~120 cm in length) after carrying outASTM E970-08A test. Sample passes burn test if less than 41 cm burned.

The Control sample is prepared entirely from old news papers (ONP). The36% SW sample is prepared from 36% unrefined virgin softwood pulp fibersand 64% ONP. The 60% SW sample is prepared from 60% unrefined virginsoftwood pulp fibers and 40% ONP. The 80% SW sample is prepared from 80%unrefined virgin softwood pulp fibers and 20% ONP. The 100% HW sample isprepared from 100% unrefined virgin hardwood. The 100% HSW sample isprepared from 100% of a mixture of unrefined virgin hardwood andsoftwood pulp fibers (75% hardwood and 25% softwood). The 50% HSW-WAsample is prepared from 50% of a mixture of unrefined virgin hardwoodand softwood pulp fibers (75% hardwood and 25% softwood) and 50% ONP towhich is added 6% wood ash fire retardant (based on the weight of thepulp fiber/ONP mixture). The 100% HSW-WA sample is prepared from 100% ofa mixture of unrefined virgin hardwood and softwood pulp fibers (75%hardwood and 25% softwood) to which is also added 6% wood ash fireretardant (based on the weight of the pulp fiber mixture).

As shown by the above Table, as density of the insulation pulp fibermixture decreases, the fire resistance of the mixture is also generallyreduced (i.e., becomes less fire resistant). As also shown by theresults from the 50% HSW-WA sample, as well as 100% HSW-WA sample,adding wood ash fire retardant increases (improves) the fire resistanceof these insulation pulp fiber mixtures, relative to the 100% HSW towhich no wood ash fire retardant is added.

All documents, patents, journal articles and other materials cited inthe present application are hereby incorporated by reference.

Although the present invention has been fully described in conjunctionwith several embodiments thereof with reference to the accompanyingdrawings, it is to be understood that various changes and modificationsmay be apparent to those skilled in the art. Such changes andmodifications are to be understood as included within the scope of thepresent invention as defined by the appended claims, unless they departtherefrom.

What is claimed is:
 1. An article comprising a fire resistant cellulosicfiber thermal insulation material comprising: a fibrous web providing anR-value (as measured by the ASTM C518 test) of at least about 3 andcomprising: from about 5 to about 85% unrefined virgin softwood pulpfibers by weight of the fibrous web; and from about 15 to about 85%unrefined virgin hardwood pulp fibers by weight of the fibrous web; andat least about 1.5% by weight of the fibrous web of a wood ash fireretardant component in and/or on the fibrous web and sufficient toimpart at least partial fire resistance (as measured by the ASTME970-08A test) to the fibrous web.
 2. The article of claim 1, whereinthe fibrous web comprises from about 10 to about 60% softwood pulpfibers and from about 40 to about 90% hardwood pulp fibers.
 3. Thearticle of claim 2, wherein the fibrous web comprises from about 15 toabout 30% softwood fibers and from about 70 to about 85% hardwoodfibers.
 4. The article of claim 1, wherein the fibrous web provides anR-value in the range of from about 3 to about 4.5.
 5. The article ofclaim 4, wherein the fibrous web provides an R-value in the range offrom about 3.4 to about 4.2.
 6. The article of claim 1, wherein thefibrous web has a basis weight about 850 gsm or less and a moisturecontent of less than about 20%.
 7. The article of claim 6, wherein thefibrous web has a basis weight about 500 gsm or less and a moisturecontent of less than about 12%.
 8. The article of claim 1, wherein thefibrous web includes one or more debonder surfactants in an amount(based on the fibrous web) of from about 0.05 to about 0.35% by weight.9. The article of claim 8, wherein the fibrous web includes one or moredebonder surfactants in an amount (based on the fibrous web) of fromabout 0.75 to about 0.15% by weight.
 10. The article of claim 1, whereinthe wood ash fire retardant component is present in and/or on thefibrous web in an amount of from about 1.5 to about 20%, by weight ofthe fibrous web.
 11. The article of claim 10, wherein the wood ash fireretardant component is present in and/or on the fibrous web in an amountof from about 1.5 to about 5%, by weight of the fibrous web.
 12. Thearticle of claim 10, wherein the wood ash fire retardant componentcomprises one or more of: calcium carbonate; potash alum (potassiumaluminum sulfate); sodium carbonate; clay; or talc.
 13. The articleclaim 1, wherein the fibrous web includes one or more other fireretardants in an amount sufficient to pass the ASTM E970-08A test. 14.The article of claim 13, wherein the other fire retardants are one ormore of: borate fire retardants, phosphorous fire retardants,halogenated fire retardants, or metal oxide fire retardants, and whereinthe other fire retardants are present in and/or on the fibrous web in anamount (based on the fibrous web) of from about 15 to about 25% byweight.
 15. The article of claim 14, wherein the other fire retardantsare present in and/or on the fibrous web in an amount (based on thefibrous web) of from about 15 to about 18% by weight.
 16. The article ofclaim 14, wherein the other fire retardants comprise one or more boratefire retardants.
 17. A process comprising the following steps: a.providing a fibrous web providing an R-value (as measured by the ASTMC518 test) of at least about 3 and comprising: from about 5 to about 85%unrefined virgin softwood pulp fibers by weight of the fibrous web; andfrom about 15 to about 95% unrefined virgin hardwood pulp fibers byweight of the fibrous web; and b. treating the fibrous web with a woodash fire composition comprising a wood ash fire retardant component suchthat the wood ash fire retardant component is present in and/or on thefibrous web in an amount of at least about 1.5%, by weight of thefibrous web and sufficient to provide a cellulosic fiber thermalinsulation material which is at least partially fire resistant (asmeasured by the ASTM E970-08A test).
 18. The process of claim 17,wherein the fibrous web of step (a) is formed from a pulp slurry, andwherein step (b) is carried out by adding the wood ash fire retardantcomposition to a pulp slurry.
 19. The process of claim 18, wherein step(b) is carried out by adding a portion of total wood ash fire retardantcomponent to the pulp slurry, and by adding the remaining portion of thetotal wood ash fire retardant component to the formed fibrous web. 20.The process of claim 19, wherein step (b) is carried out by adding fromabout 5 to 100% of total wood ash fire retardant component to the pulpslurry, and by adding from 0 to about 95% of the total wood ash fireretardant component to the formed fibrous web.
 21. The process of claim20, wherein step (b) is carried out by adding from about 10 to about 90%of total wood ash fire retardant component to the pulp slurry, and byadding from about 10 to about 90% of the total wood ash fire retardantcomponent to the formed fibrous web.
 22. The process of claim 18,wherein step (b) is carried out by using a size press to add theremaining portion of the total wood ash fire retardant component to theformed fibrous web.
 23. The process of claim 18, wherein step (b) iscarried out by spraying the remaining portion of the total wood ash fireretardant component on the formed fibrous web.
 24. The process of claim17, wherein step (b) is carried out by treating the fibrous web with thewood ash fire retardant composition such that the wood ash fireretardant component is present in and/or on the fibrous web in an amountof from about 1.5 to about 20%, by weight of the fibrous web.
 25. Theprocess of claim 24, wherein step (b) is carried out by treating thefibrous web with the wood ash fire retardant composition such that thewood ash fire retardant component is present in and/or on the fibrousweb in an amount of from about 1.5 to about 5%, by weight of the fibrousweb.
 26. The process of claim 25, wherein step (b) is carried out bytreating the fibrous web with a wood ash fire retardant compositionwherein the wood ash fire retardant component comprises one or more of:calcium carbonate; potash alum (potassium aluminum sulfate); sodiumcarbonate; clay; or talc.
 27. The process of claim 17, which comprisesthe further following step: (c) treating the fibrous web with one ormore other fire retardants in an amount sufficient to pass the ASTME970-08A test.
 28. The process of claim 27, wherein step (c) is carriedby treating the fibrous web with one or more of: borate fire retardants,phosphorous fire retardants, halogenated fire retardants, or metal oxidefire retardants, in an amount (based on the fibrous web) of from about15 to about 25% by weight.
 29. The process of claim 28, wherein step (c)is carried by treating the fibrous web with one or more of: borate fireretardants, phosphorous fire retardants, halogenated fire retardants, ormetal oxide fire retardants, in an amount (based on the fibrous web) offrom about 15 to about 18% by weight.
 30. The process of claim 28,wherein step (c) is carried by treating the fibrous web with one or moreborate fire retardants.
 31. The process of claim 17, wherein the fibrousweb of step (a) comprises from about 10 to about 60% softwood pulpfibers and from about 40 to about 90% hardwood fibers.
 32. The processof claim 31, wherein the fibrous web of step (a) comprises from about 15to about 30% softwood pulp fibers and from about 70 to about 85%hardwood fibers.
 33. The process of claim 17, which comprises thefurther following step: (d) treating the fibrous web with one or moredebonder surfactants.
 34. The process of claim 33, wherein step (d) iscarried out by treating the fibrous web with the debonder surfactants inan amount (based on the fibrous web) of from about 0.05 to about 0.35%by weight.
 35. The process of claim 34, wherein step (d) is carried outby treating the fibrous web with the debonder surfactants in an amount(based on the fibrous web) of from about 0.075 to about 0.15% by weight.36. The process of claim 17, which comprises the further following step:(e) treating the fibrous web with one or more trivalent metal cations.37. The process of claim 36, wherein step (e) is carried out by treatingthe fibrous web with alum.